Overlooking parliament square with a clear view of Big Ben, NIOC House on Victoria Street is advertised as one of the best-located office blocks in central London.
It would take a close observer to figure out that the building belongs to the National Iranian Oil Company and is part of a now depleted worldwide portfolio that the Islamic Republic has owned through decades of isolation and international sanctions.
The building is rented to commercial tenants as well as providing top floor offices for the state-run company. It has also provided a venue for the British-Iranian Chamber of Commerce (BICC), a body chaired by Norman Lamont, the former Conservative chancellor of the exchequer.
The BICC maintains an active website, where Lord Lamont last posted early this month about the implications of the European launch of the Instrument for Supporting Trade Exchanges (Instex) designed to support trade with Iran in the face of US sanctions imposed after withdrawing from the 2015 nuclear deal.
"Although a number of operational details need to be addressed, the launch of Instex is significant and encouraging to those of us who believe that the UK must honour its commitments under [nuclear deal] and that the overwhelmingly pressing sectors to address must be those of a humanitarian nature," he wrote in a cautious welcome. "In time, it may be available for trade in other unsanctioned items."
The BICC's Twitter feed and calendar of events however appears to have ground to halt shortly after President Donald Trump pulled Washington out of the nuclear deal last May.
Other relics of the Iranian presence in London are dotted around the capital.
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